Optimization of a model internal combustion engine

Abstract
We optimize the operating conditions of a model internal combustion engine to obtain maximal efficiency. The model engine consists of a cylinder equipped with a piston containing a working fluid, coupled to a heat bath and heated by internal combustion with a rate of heating that is very weakly dependent on the temperature and pressure of the working fluid. We consider operation of the piston under the influence of an external pressure. The model engine includes valves allowing the exhaust and intake of the working fluid. It is found that the optimal operation has an optimal compression ratio and an optimal energy to be exhausted with the working fluid. The results are demonstrated with a numerical example. Also presented are optimizations for this system of the average power, and optimization of the work for a given specified average power.